292 
Journal of Agricultural Research 
Vol. XXI, No. S 
the com germ supplied 6.97 pounds of ash in addition to that present in 
the com, yet this ash contained only 0.03 pound calcium, an inadequate 
amount. The casein furnished only 0.36 pound ash and the milk 
albumin 0.71 pound. These amounts were inadequate for the needs 
of the growing pig. All the pigs which attained a growth of 210 
pounds or more had an abundance of ash in the ration. 
Proportionately there is a smaller change in the ash percentage than 
in the percentage of moisture and fat. 
ASH PERCENTAGES ON THE BASIS OF EMPTY WEIGHT, LESS FAT 
The gradual decrease in ash percentages as the pigs increase in size is 
almost wholly due to the large increase in percentage of fat. In Table 
V the percentage of ash is calculated on the basis of empty weight less 
fat, or the relation of ash to the amount of body substance less fat. 
These results are plotted in figure 4. The general direction of this curve 
shows that the ash percentage tends to remain constant in the tissues of 
the body not fat. 
PROTEIN CONTENT 
The figures for percentages of protein given in Table III are plotted in 
figure 5. With a few exceptions, the protein curve has the same general 
direction as the moisture curve. As pigs increase in size the percentage 
of protein decreases. This is due to the relatively large increase of fat. 
The figures for the percentages of protein on the basis of empty weight 
less fat are given in Table V, and the curve is given in figure 6. The gen¬ 
eral direction of this curve is practically straight. In this respect it is 
similar to the curve for ash on the basis of empty weight less fat. 
CONCLUSIONS 
The data presented permit the following conclusions: 
1. Pigs fed rations decidedly deficient in ash or protein had a very 
restricted growth. The composition of their bodies was characterized 
by wide variations among the different animals, generally a low fat and 
a high moisture content. 
2. Pigs fed a partially deficient ration, but one which was sufficient 
to produce a restricted growth, had a high fat content. 
3. In pigs fed a ration that was balanced in respect to the protein 
and ash requirements, the moisture and fat content were nearly equal, 
with a tendency for the fat percentage to be a little lower than the 
moisture percentage. In pigs whose ration was partially restricted, the 
fat content was higher than the moisture content. This statement ap¬ 
plies only to pigs weighing less than 225 pounds. 
